Stapling machine



Aug. 30, 1932. w; RANNEY 1,874,622

"smrmne' MACHINE 'Filed'uarch 2, 1931 '7 Sheets-Sheet l Aug. 30, 1932- w. B. RANNEY 1,874,622

STAPLING MACHINE Filed March 2, 1931 7 Sheets-Sheet 3 Aug. 30, 1932. w. B. RANNEY 2 STAPLING MACHINE Filed March 2, 1931 7 Sheets-Sheet 4 9Q n o o 0 gm n Q X Aug. 30, 1932. w. B. RANNEY 1,8745622 STAPLING MACHINE Filed March 2, 1931, 7 Sheets-Sheet -S I Ewe/722504 Aug. 30, 1932. w. B1 RANNEY 1,874,622

STAPLING MACHINE Filed March 2, 1931 7 Sheets-Sheet 6 1932, w. B. RANNEY EifiWfiZ? STAPLING MACHINE Filed March 2, 1951 7 sheets sn et 7 Patented Aug. 30, 1932 hairs; "stares IIPATENTISFMQE "EIIZLET B. BANNEY, OF CHICAGO, ILLINOIS, ASSIGNOR 'TO NM. WRIGLEY JR. GOMr;

PANY, G1 CHICAGO, ELLINOIS,.A-CORPORATIOII OF DELAWARE s'mrnnve MACHINE;

' Application filed. March 2:,--1931. Seria1 No. 519,346.

This invention relates to improvementsin stapling machines, and more particularly to an automatic machine for .assemblingand fastening partsofboiies and like articles with greater efiiciency and increased production than is possible with the more common hand feeding types Of stapling or stitching ma chines, in that it eliminates the manual labor and is more rapid and continuous inits operation. f v

The machine of the present disclosure is one especially designed iorthe operation'of stapling cardboard panels or cards to boxes later to be filled with packaged goods. The cards are folded over the contents during shipment, and serves as a display sign when the goods are on sale. However, the same mechanism may bB U EIhZQCl for other automatic stapling, stitching or fastening operations.

A preferred embodiment of the invention is disclosed in the accompanying drawings, in which: K V

Figure 1 is' a general top plan View of the machine;

Figure 2 machine. p 7

Figure 3 is a view of the machine in vertical-section as taken online 3*? of'Figure 1.-

- Figure 4 is an enlarged detail 'iew in horizontal section "as taken on line 44- of Fig ure 3.

Figure 5 is an enlargeddetail view in vertih cal section as taken on line 55 of Figure d showing the pos tions of the card transfer memherin approaching the end of its movement to'and from staplin position.

Figure 6 is a. view similar to Figure-5 showing the transfer member in stapling position and about to remove a card from the bottomof the stack in the magazine.

Figures? and 8 are diagrammatic views showing the progress of the boxes through themachine, and

- Figure 9 is a perspective view of a finished box with its ii stapled in place. p J .L J Piezerrmg to the general arrangement of the machine, Figures 1, 2 and rd in its desi in consisting of a hollow L- is a view in end elevation of the 0, me stapling stitching HIGCllZUllSIfl is more or less standshapedirame supported upon a table 2 which in turn is supported upon a pedestal 3- .beneaththe baseoif the L-trame having a base plate 4 extending-well forwardly'beyond the stapling head 5 mountedat the end of the horizontal-arm 150i 'said frame. The stitch-- .ing or staplinghead 5 is of standard construction and design; and therefore will not I be described indetail, other than to point out that-itfis preferably of the duplex type, that is, c'apableof driving two staples on each- Y operation, the wire being fed from two spools:

6, 6positionedabove the head and mounted on a bracket 7 fixed'to thearm'lbof the L-' frame 1 to a pair of verticallyarranged staple driving members 5a, 5a operating simulta-: neously to-cut anddrivethe staples down wardly through the overlapping portions of the boxes-and cards as they are succesively advanced and assembled beneath the stapling headr 'Theistapling mechanism is driven through a shaft "8 extending lengthwise-of the horizontal -arm lb of the L-frame, and-- having alarge'gear 9-lo0sely mounted on the A rear end thereof.-?T his gear wheel has direct .drivingconnection with a motor 10 mounted at the r'earof the table 2 and having a pinion I lOwmeshin'g withsaid gear'wheel 9. A clutch mechanism '11 is interposed between the loose gear wheel 9- and the shaft 8, and is actuatedward edge of the elongated table 2 is mounts ed the box feedingmechanism, including gen erally a trackway leading to and beyond the 1..

staplinghead 5, andmeans for advancingthe boxes successively along the trackway and into stapling position.

Before the cards, orflies as they are called, are stapled to the boxes, the latter are shallow open cardboard containers which preferably have been covered or coatedwith a surface wrapper in any standard wrapping machine. In fact,=it is preferable, although not neces box is discharged from the wrapping machine sliding endwise on its bottom, it is, deposited in front of the pusher blade13 just as it advances forwardly with a quick movement, so

=that without turning the box it reaches the end of the track in the transverse position shown in Figures 7 and 8. 7

Now, immediately below the delivery track 12 and extending along the front edge of the table 2 is a narrow upwardly facing trackway 13 extending, the full length of the machine and beneath the stapling head. The track is defined between upright guide bars, the rear bar 14 being straight and extending along the'rear edge of the track surface (Figure 3) and while the front guide bar 15' is relatively narrow and extends throughout the section immediately below the stapling head, therebeing other guide plates for directing the path of the boxes as they approach the" stapling position. Moving longitudinally of thespace above the trackway 13 is a reciprocating carrier 16 consisting of a light metal casting having a horizontal edge portion 16a forming a support for the boxes on edge and two vertical portions 16?) and 160 formingpusher members at each end. The

carrier is fixed to a sliding carriage 17 traveling on apair of spaced rods 18, 18 extending thelength of the table 2 and immediately to the rearof the trackway 13, and supported at their ends in brackets-18a, 18a. The carriage 17 has the form of a pair of connected sleeves having a short transverse arm 19 at its forwardend connected with the adjacent end of the box carrier 16 (Figure 4).

The carriage is actuated through mechanism consisting'of an upright rocking lever 20 connected at its upper end with the carriage by ashort 1ink21, and mounted at its lower end on a stub shaft 22 journalled in a bracket 23 mounted on top of a bearing stan dard 24 fixed to the floor adjacent the left end of the machine (Figure A'drive shaft 25 is journalled at one end in said bearing standard 24 and at its opposite end in a similar bearing standard'26, and' fixed to this shaft is a cylindric cam 27 having a groove 27a engaged by a cam roller 28a at the stub shaft end of a rocker arm 28, whereby a rocking movement is imparted to therlever 20 and areciprocating movement to the carrier 16. The shaft 25 is driven from a motor or othersuitable source of power, as

by a chain drive, the sprocket wheel 29 being mounted at one end of the shaft.

As already explained, the boxes are pushed to the end of the upper track 12, and on reaching this point, negotiate a downward turn which deposits them on edge upon the carrier 16 which at the instance is in its starting or retracted position opposite the end of said track 12. In this passage the boxes are guided by a pair of upright guide bars 30, 30 which extend forwardly and then curve rather sharply in a downward direction, at the same time deflecting rearwardly toward the top edge ofthe carrier so that each box comes to rest upon the carrier 16 on edge with its open side facing outwardly, as shown in position A, (Figure 7), the carrier immediately moving laterally toward the stapling head carrying the box tothe p'ositionB, (Figure 8).

Now, immediately behind the path of the boxes in their movement on the carrier 16, and extending upwardly from the rear guide rail 14- isa rectangular plate 31v somewhat longer than the boxes, but of practically the same width. Opposite this plate are guide bars 32 forming therewith a walled space into which the boxes enter in passing from positions A to B, the bars being bent at their ends to provide stops 32a extending across their paths to bring the boxes to rest in position B.

Near'the top edge of the rear plate 31 is a slot 31a through which projects one arm of a spring actuated presser foot 33 having the form of a bell-crank lever pivotally mounted on a bracket 33a fixed to the back of the plate at'the' forward end of the slot (Figure 4). ,One arm of the lever forms a shoe 331.- which normally projects edgewise through the slot into the path of the boxes and held normally in that position by a spring 34 connectedwith the. shorter arm of said lever.

Fixed 'to the forward end of the sliding carriage 17 is a bar 35 projecting forwardly beyond the carrier 16 which is also part of the reciprocating box feeding mechanism. The endof this bar is turned upwardly and carries an adjustable abutment screw 35a adapted to engage the rearwardly projecting arm of the presser foot lever 33 to swing the shoe 335 out of box engaging position just at the instant that the box carrier has reached the end of its return stroke (Figure 7).

.Thus it will'be observed that as each box reaches the position B (Figure 8) at the end of the forward stroke of the carrier, it

is held in that positionby the presser foot forcing it against the front guide bars 32, whereupon the carrier returns to its starting position, leaving the box suspended in position B until the presser foot is released by the contact member 35a, whereupon it drops by gravity onto the trackway 13 to position B, just as the next box is deposited onto the carrier in position A. The box in position B igure 7) is thus dropped in front: ofithe front pusher..1'60 of the carrier',-,

so thatas the carriermoves forwardly it si-i multaneously advances .the preceding box fronrposition B to C, andathe following box'fromposition A to B. Now, position 0 is directlywbeneath the stapling head 5 in which the boxes are stationed during the stapling'operation. Manifestly as each box is advanced into stapling position C, it pushes the one ahead of it out of that positioninto positionl);

And finally on reaching the station beneath the stapling head (position C) a card or fiy'i's-assembled or applied to the box just before the stapling head drives the staples and the operation is completed (see Figure 9). -The'mechanism for feeding the cards or flies will now be described:

Immediately in front of the stapling head is a- 'magazine 36 mounted at-the upper end of a frame'made up of angle bars 87, 37 eX- tending forwardly and upwardly at an angle of approximately 30 to the vertical and anchored at their lower ends to a bracket 38 bolted tothe forward-edge of the base plate 4, and supported by a brace member '39 eX- tending forwardly from the table 2. The magazine 36 is an open rack in which a stack F ofthe cards or flies f is placed, the stack owing to the inclination of the magazine supportingframe being also inclined so thatthe plane :ofv the bottom of the stack is about 30 "to the horizontal. The bottom of the magazine is open so that the lowermostcard is always exposed from below, the stack beingheld merely by short inwardly project-' ing fingers. 36a (Figure 4) Now, moving in a path between the bottom of the magazine 36 and a position below and adj acent-the stapling head 5, is a suction actuated: transfer member in the form of a cylindric head 40 mounted at the upper end of a fvertical bar 41"adaptedtotravelzback.

and" forth :with a combined oscillating and endwise movement between the magazine and the stapling head. The suction head 40 is essentially hollow cylindric member having a perforated face directed upwardly and a hose 42 connected therewith which leads to a'source ofreduced air pressure such as a compressor. Thus when the suction head is brought into contact with-the bottom of the .drivenshaft 25, where it has pivotal connection with an eccentric crank pin 43 at one end of a counter-shaft 44 driven from the main ure 5.

:shaft25 through appinion 45, meshing with a gear. wheel 46 on said shaft25 (Figure 3).. The throw of the crank is relatively small but suflicient to impart the required endwisemovement to the supporting bar 41. An osclllatlng or rocking movement is impartedto the bar 41 through cam actuated rocker arm 47 pivotally mounted at its lower end on a bearing shaft 48. (Figs. 2 and 3.) andv carrying arcam roller 47a near its lowerend which coacts *ith a plate cam 49 mounted on the shaft 25 to lmpart a rocking motion tov The upper end of the lever is staple driving members 56:, 5a of the stapling head. -These anvils are of the usual shape employed in stapling machines and serve to turn the prongs of the staples inwardly after they have been driven through the layers being stitched or bound together.

Referring now to Figures 5 and-6, the

movement of the suction head as it travels towardthe magazine 36 is in a general on"- ward and downward direction until it reaches the position shown in dotted lines in Fig- At this point the rocking movement ceases momentarily and the endwise movement-becomes effective through the crank motion, thus elevating the suctionhead almost in .a straight line into contact with the lowermost card of the stack as shown in dotted lines in Figured This upward movement of the suction head is partially assisted or directed by a guide bar 53 depending from the outer edge'of the magazine and a roller 54 mounted caster-hire ust below the suc- 'tion head 40, and positioned so that it comes:

into contact with the guide 53 and thus directs the suction head into contact with the bottom of the stack in the magazine, whereby the lowermost card is removed, preparatory to being carried forwardly to the stapling head.

To aid in the removal of the cards from the magazine, it is preferred to direct a stream of air from a nozzle 55 between the last few cards, thus separating them sufiiciently to insure the removal of the bottom sheets by suction and against any adhesion that might prevent removal. The air nozzle is supported by a suitable bracket 55a mounted on the magazine, and an air supply hose 56 leads to a small auxiliary air pump 57 (Figure l) belt driven from a countershaft 58 connected with the main drive shaft of the stapling head through a pinion p59 meshing with the gear wheel 9.

5 and thence moves vertically into stapling position with the marginal portion of the card f projecting into and lying flatwise against the inside of the upper side wall of the box, as shown in Figures 6 and 9. As a means of guiding the suction head to its position beneath the stapling head, rollers 60, are

mounted on the ends of the cross bar 51 which carries the anvils 52, these rollers engaging a pair of vertical guide rails 61, 61 supported by angle brackets 61a mounted on the magazine frame brace 39. Also to aid in holding the boxes immovable during the stapling operation, a fixture 62 is mounted centrally of the cross bar 51 and adapted to register with the central portion of the box, said fixture having laterally projecting curved sprlng fingers 62a, 62a adapted to bear against the' bottom of the box, holding it against the back rail 14 and at the same time flexing into contact with the end walls of the box, thus centering it in stapling position should there be a slight displacement.

Now, as the several driving and actuating mechanisms are timed, the stapling operation takes place the instant after each card is \brought into register with the wall of the box, two staples s, 8 being driven through the twothicknesses of cardboard, as shown in Figure 9, the suction head holding the card during the stapling operation, and then breaking contact as it is drawn away to start its next stroke to the magazine. In the meantimethe finished box is pushed onward- 'ly to the right to position D (Figures 7 and 8) 'bythe next box being advanced into stapling position C.

Now, as is the usual practice in the design of automatic machines, provision is made for temporarily interrupting the action of one or more of the operating parts in the event of improper feeding of the materials, in this case it being chiefly the irregularity in the feed of the boxes to the stapling head which would cause difficulty unless guarded against. Thus means are employed for venting the suction line, which renders the head 40 incapable of removing the cards from the mag azine, and at the same time actuates a trip mechanism which throws out the clutch controlling the drive to the stapling head. The

closed or sealed by a valve member 64 projecting beneath thevback rail 14 and into the pathof the boxes as they reach the station beneath the stapling head. As shown in Fig .ure 4, the valve member is held over the end of the pipe 63a by the pressure exerted by the boxes, and also against the tension of a spring 66 acting on the'valve member. Thus should a box fail to be fed into stapling position, the suction line would be Vented by the uncovering of the end of the vent pipe 63a by the valve member 64 actuated by the spring 66, from which itfollows that no card f would be transferred from the magazine by the suction head during the stroke which 1 I normally would i have been applied to the missing box.

Now, referring'again to the drive for stapling head, the clutch mechanism 11 is of the free running type, that is, it normally allows thegear'wheel 9to turn freely on the driven shaft to the head, and intermittently drives the stapling 'mechanism as the clutch is thrown in and out by a vertical push rod 67 extending from the clutch to the base of the machine 'where it is connected with a rock lever 68 journalled intermediate its ends on the bracket 26. The forward end of the lever 1 arm carries a cam roller 68a bearing against the periphery of the circular plate cam 49, the same having a projection 69 acting during each revolution to rock the lever 68 and impart an upward stroke to the push rod 67. Further details of the clutch mechanism is unnecessary-as it is a type used extensively in punching, stamping and stapling machines. However, the push" rod 67 is divided into sections having telescoping end portions, a pawl cylinder connects with another branch pipe 63?) from themain suction pipe 63, so that under normal operating conditions'the suction acts to draw the piston to the left (Figures 1 and 2), and against the tension of a coilspring 74 also connected with the piston rod and exertinga force opposing that exerted by the suction within the cylinder; Now, if the suction line should be vented by the failure of a box to be fed into the stapling station, it follows that the suction would be relieved in the cylinder, and the spring 74 would then act to move the dog 71 and thus trip the pawl 70, thus disconnecting the two sections of the push rod 67 As a result the lower section of the rod would continue to move with each oscillation of the lever 68, but the upper section would remain stationary, so that the clutch 9 will not operate to throw the stapling mechanism into ac:

u *tion, as longasthe boxes fail to be fed beneath the stapling head.

. And -finally,'t0 insure the discharge of a box from the stapling station C (Figures 7' and 8), should a vacancy occur in the positionB just preceding, a long thin blade 7 is attached to the forward end of the box carrier 16 (Figure 4) sothat it lies between the back rail 14 of the trackway and the boxes as they travel from position B to-C. This blade is slightly longer than the length of" the boxes and is bowed just enough. so

I that in the absence of'a box it would be free to spring outwardly toward the center of the trackway. Now, in normal operation the box in position B is carried forward by thecarrier 16 into stapling position 0, and in so doing pushes the box just stapled ahead of it into a position D; But if there should be a vacancy in the feed line of boxes, it follows that if there should be no box advanced from position B, the box in position would remain in its position and the stapling operation would be repeated, were it not for the blade 75, which, taking the place of the absent box, would abut against the finished box in position C and move it to position D, so there would be no interruption in the progress of the box immediately ahead of the vacancy.

As the operation of the machine has been described, it is contemplated that the suction exerted on the cards 7 by the head of the transfer mechanism in carrying the same from the magazine 36 to stapling position beneath the stapling head 5, is not so great as to interfere with the parting orwithdrawal of the head from the cards after the stapling operation, that is, without a tend- I may be necessary under certainconditions to V insurethe separation by reheving the suct on ency to tear the cards from the box or bend them; Ordinarily this is the case, but it for an instant just as the stapling operation takes place, this being accomplished'by venting the suctionline'leading to the head 40 -which, as already described, consists of the base 42 connected with the pipe 63 leading to asuitable source of reduced air pressure.

- Referring to Figure-1, it will be noted that the suction pipe 63 is divided into branches arranged in a T, one branch pipe 7 6 leading rearwardly to a source of suction, and the other, a short branch pipe 77, leading for- V wardly to a point just rearwardly of the rev --a flap valve 78 in the form of a small metal plate hinged at one end on a narrow stripciprocating cross head 17 which actuates the box feeding pusher plate 16. greater detail in Figure 4, the end of'this branch base pipe 77 terminates in a nozzle. 7700 having an upturned ventlike fittin opening. Glounted adjacent this filling is orplate 79 extending lengthwise-0f the machine parallel with the bearing rods 18, 18, 65.

and anchored to the machine frame vby means As shown in v of bolts 80 passing through slots 79a in the ends of the plate. I The flap valve member 78extends longitudinally of the plate 7 9 and has a hinge'78a at one end and an extension 785 at its oppo' site end. The valve member normally rests upon the fitting 77a and closes the vent openin Mounted on the cross head 17 is a trip finger 81 extending rearwardly at right angles to the direction of travel of said cross head and terminating in a roller 81a in line with the extension 78a of the flap valve so that with each stroke of the cross head 17 in one direction, namely, to the left, the trip finger-81 lifts the flap-valve member and uncovers the opening inthe upturned end in the fitting 7701, thus venting the suction in the pipe 63 and the hose 42 leading to the suction head. Now this venting of the suction line is only momentary and is timed to take place just as the stapling operation is completed, thus allowing the suction head to be withdrawn from the card just stapled, and for the obvious purpose of facilitating the parting of 7 one from the other as the suction headAO starts its return movement toward the magazine 36 for the next-card.

Thus in the machine herein disclosed, provision has notonly been made for the -con-. tinuous feeding and stapling of boxes and their flies, but also in guarding against faulty operation and possible damage to; the machine, by automatically interrupting theaction of the essential parts, should a break "mechanism, means for advancing boxes inter- .mlttently along sald trackway to a station beneath said stapling mechanism, a card magazine ad acent said trackway, and a card feeding member adapted to oscillate betweensaid ;magazine and the position of said boxes on said trackway beneath said stapling mechanism.

2. In a stapling machine, the combination intermittently acting staple driving means,- means for feeding boxes into stapling position, a card-holding magazine, anoscillat1ng transfer member comprising a card engaging member having a suction head s adapted to transfer the cards from the magazine to the boxes and hold the same in position during the stapling operation.

3. In a stapling machine, the combination of stapllng mechanism, means for continuously feeding boxesto said stapling mechanism, a card magazine, a card transfer member adapted to'travel between said magaj zine andsaid stapling mechanism and includ ing a suction activated gripper member for 5 removing successlve cards from the bottom of 'the magazine and positioning the samein contact with each box for stapling, said gripper member communicating with a source of reduced air pressure, and means for relieving the suction when a box fails to be presented for stapling.

4. In a stapling machine, the combination of stapling mechanism. means for continu ously feeding boxes to said stapling mecha= nism, a card magazine, a card transfer member adapted to travel to and from said magamechanism;

5. In a box stapling machine, the combination of intermittently acting staple driving mechanism, a trackway extending to and from said staple driving mechanism, means for feeding boxes to said trackw'ay, a reciprocating carrier moving longitudinally of said trackway for advancing the boxes successively into stapling position, a card ma azine and a suction activated member or transferring cards from said magazine to.

said boxes in stapling position.

a 6. In a box stapling'machine, the combination of intermittently acting staple driving mechanism, a trackway extending to and fromsaid staple driving mechanism, meansfor feeding boxes to said trackway, a reciprocating carrier moving longitudinally of Y as ' said trackway for advancing the boxes successively into stapling position, a card magazine, means for transferring cards from said magazine to said boxes in stapling position, and means dependent upon the presence of a box in its stapling position for controlling the action of said card transferring member. a 7 In a box stapling machine, the combination of intermittently acting staple driving mechanism, a trackway extending toward said staple'driving mechanism, means for feeding boxes to said trackway, a reciprocating carrier moving longitudinally of said trackway for advancing the boxes successively into stapling position, a card magazine removed from said trackway and opposite said stapling mechanism, an oscillating carrier moving to andfrom said magazine and having)a contactv member adaptedto grip the cards y adhesion, and to transfer the sameto the boxes in stapling position, and means dependent upon the presence of a box in stapling position for controlling the degree of adhesion exerted by said contact member on said cards. T v v y 8. 'In'a stapling machine, the combination of a stapling head including staple driving members,;a trackway extending horizontall beneath said stapling head, means for a vancing boxes to be stapled along said trackway, a card holding magazine located adja cent said stapling head, an oscillating transfer member moving to and from said magazine and transversely of the path of the boxes along saidtrackway, and comprising a suc tion head adapted to grip the cards flatwiseat the bottom of the magazine and present them to'the boxes in position for stapling, a pipe connecting said suction head with a source of reduced air pressure and having'an intermediate vent opening and arvalve foi said vent opening and normally held in closed position by the contact with a box in stapling (position, and a spring acting to open sai valve member to ventsaid suc tion head'in the absence of a box in said Stapling position. I I a L v 9. Ina stapling machine, the combination of a stapling head including staple driving members, a trackway extending'horizontalliy beneath said stapling head, means for a vancing boxes to be stapled along said trackway including a reciprocating carrier, a card holdin magazine located adjacent said stapling end, an oscillating transfer member moving to and from said magazine and trans versely of the path of the boxes along said trackway, and comprising a suction head adapted to grip the, cards flatwise at the bottom of the magazine and present them tothe boxes in position for stapling, a pipe con necting said suction head with a source of reduced air pressure, and having a branch vent pipe terminating adjacent the station occupied by the boxes for stapling, a spring actuated valve member having a portion pro jecting into the path of the boxes and actin to close the vent pipe by the pressure of a ox exerted thereon, and to open the vent pipe to thereby decrease the suction at said head and thus prevent the transfer of a card from said magazine in the absence of a box in position for stapling.

10. In a stapling machine, the combination of staple-driving mechanism, means for feeding boxes toward stapling position ad-" jacent said staple driving mechanism including a reciprocating feeding member, means for feeding cards into position for staplin to said boxes comprising an oscillating suct1on head movable between a card supply and said stapling position, a suction pipe leading from asource of reduced air pressure to said suction head and provided with a vent, a valve normall closing said vent and a trip member carrled by said reciprocating box feeding member and operative to trip said valve and to vent said pipe after each stapling operation.

11. In a stapling machine, the combination of staple-driving mechanism, a source of power for driving said staple-driving mechanism, clutch interposed between said source of power and said staple-driving mechanism and normally disconnecting the same, driving means for operating said clutch to effect the intermittent operation of said stapledriving mechanism, means for feeding boxes toward a stapling position adjacent said stapling mechanism, and suction actuated tripping mechanism associated with said clutch operating mechanism and operative inthe event of failure of a box to be fed into stapling position to prevent the operation of said stapling mechanism.

12. In a stapling machine, the combination of stapling mechanism, a motor driving said stapling mechanism, a clutch interposed between said motor and stapling mechanism, clutch controlling mechanism including a reciprocating push rod acting to alternately release and engage said clutch to effect the intermittent action of said stapling mechanism, suction-actuated mechanism normally acting to retain said push rod in operative connection with said clutch, and means for controlling the suction-actuated mechanism comprising a vent pipe and a valve in said vent pipe located adjacent the path of said boxes and normally held in closed position by contact therewith.

18. In a stapling machine, the combination of stapling mechanism, a suction for driving said stapling mechanism, a clutch intel-posed between said suction and stapling mechanism, driving mechanism including a reciprocating push rod for alternately releasing and engaging said clutch to efiect the intermittent action of said stapling mechanism, said push rod including a pair of telescoping sections, a pawl normally locking said sections together as a unit, a suction-actuated piston connected with said pawl and normally acting to hold it in locking position against said suction-actuated member, a spring acting on said pawl and opposing the force of the suction, and means for controlling the suction comprising a vent pipe, and a spring-actuated valve for said vent pipe located adjacent the path of said boxes and normally held in closed position'by contact therewith.

Signed at Chicago, 111., this 30th day of January, 1931.

WILLET B. RANNEY. 

